Fig. 36. 



Fig. 37. 



Fig. 38. 



Fig. 39. 







- * * ... -.- • '' ' 





••■"*- 



(. 



W 





Magnification, 72 x (see remarks on preceding page). Fig. 37, etched with ammonia and 

 hydrogen peroxide, followed hy acidified ferric chloride. Figs. 38, 39, etched with ammonia 

 and hydrogen peroxide. 



